Synthesis of poly-3-hydroxybutyrate (PHB) by <i>Bacillus cereus</i> using grape residues as sole carbon source

Polyhydroxyalkanoates (PHA) are bacterial polyesters that have been described as one of the most promising sustainable alternatives to petroleum-based plastics. A major challenge for PHA become market-competitive, is decrease associated production costs. According several studies, about 20–50% total costs attributed raw materials and therefore, use different types organic residues evaluated substrates microorganisms. In this study, strain Bacillus cereus ATCC 14579 was cultivated in shake flasks using a defined medium pretreated grape peel sole carbon source. The pretreatment peels performed by hydrolysis step with diluted sulfuric acid yielding up 52.9% (w/w) sugars from dry residue. PHB extraction wet biomass showing 3.7-higher yields when latter. accumulation 18.79% (w/w), corresponding 0.53 gPHB/L, achieved hydrolyzate at 72 h cultivation. Eventually, possibility producing non-treated lignocellulosic (LCB) high contents fermentable presented an interesting alternative be optimized projected bioplastic processes.